Add access() calls to ensure fopen(...,"r") doesn't segfault

One of the invariants of the fopen() function called with the "r"
option is that the file exist before the function is called. If
this is not the case behavior is undefined (in the case of glibc
on some Crays and Redhat machines this means you get a segfault
in fileno_unlocked()). This commit is a first attempt at ensuring
this invariant holds when calls to fopen() are made.

Author: npe9

ompi/debuggers/dlopen_test.c

@@ -65,12 +65,17 @@ static int do_test(void)
 
     /* Double check that the .la file is there that we expect; if it's
        not, skip this test. */
+    if (!access(full_filename, F_OK)) {
+      fprintf(stderr,
+              "File %s.la doesn't seem to exist; skipping this test\n",
+              full_filename);
+      exit(77);
+    }
     fp = fopen(full_filename, "r");
-    if (NULL == fp) {
-        fprintf(stderr,
-                "File %s.la doesn't seem to exist; skipping this test\n",
-                full_filename);
-        exit(77);
+    if (fp == NULL) {
+      fprintf(stderr, "File %s.la fopen failed; skipping this test\n",
+              full_filename);
+      exit(77);
     }
     /* We know the .la file is there, so read it, looking for the
        dlopen value.  If the dlopen value is '' (i.e., empty), then

ompi/debuggers/ompi_debuggers.c

@@ -148,7 +148,7 @@ static void check(char *dir, char *file, char **locations)
         FILE *fp;
 
         /* Just try to open the file */
-        if (NULL != (fp = fopen(str, "r"))) {
+        if (access(str, F_OK) && (NULL != (fp = fopen(str, "r"))) {
             fclose(fp);
             opal_argv_append_nosize(&locations, file);
         }

ompi/mca/coll/tuned/coll_tuned_dynamic_file.c

@@ -88,6 +88,10 @@ int ompi_coll_tuned_read_rules_config_file (char *fname, ompi_coll_alg_rule_t**
         return (-3);
     }
 
+    if (!access(fname, F_OK)) {
+        OPAL_OUTPUT((ompi_coll_tuned_stream,"rules file does not exist [%s]\n", fname));
+        goto on_file_error;
+    }
     fptr = fopen (fname, "r");
     if (!fptr) {
         OPAL_OUTPUT((ompi_coll_tuned_stream,"cannot read rules file [%s]\n", fname));

ompi/mca/topo/treematch/treematch/tm_mapping.c

@@ -73,6 +73,12 @@ int nb_lines(char *filename)
   char line[LINE_SIZE];
   int N = 0;
 
+  if(!access(filename, F_OK)) {
+    if(tm_get_verbose_level() >= CRITICAL)
+      fprintf(stderr,"%s does not exist\n",filename);
+    exit(-1);
+  }
+
   if(!(pf = fopen(filename,"r"))){
     if(tm_get_verbose_level() >= CRITICAL)
       fprintf(stderr,"Cannot open %s\n",filename);
@@ -97,6 +103,11 @@ void init_mat(char *filename,int N, double **mat, double *sum_row)
   int i,j;
   unsigned int vl = tm_get_verbose_level();
 
+  if(!access(filename, F_OK)) {
+    if(tm_get_verbose_level() >= CRITICAL)
+      fprintf(stderr,"%s does not exist\n",filename);
+    exit(-1);
+  }
 
   if(!(pf=fopen(filename,"r"))){
     if(vl >= CRITICAL)

ompi/mca/topo/treematch/treematch/tm_topology.c

@@ -481,6 +481,11 @@ int  tm_topology_add_binding_constraints(char *constraints_filename, tm_topology
   int i,n;
   unsigned int vl = tm_get_verbose_level();
 
+  if (!access(constraints_filename, F_OK)) {
+    if(tm_get_verbose_level() >= CRITICAL)
+      fprintf(stderr,"%s does not exist\n",constraints_filename);
+    exit(-1);
+  }
 
   if (!(pf = fopen(constraints_filename,"r"))) {
     if(vl >= CRITICAL)

opal/mca/btl/openib/btl_openib_ini.c

@@ -229,9 +229,17 @@ static int parse_file(char *filename)
 
     /* Open the file */
     ini_filename = filename;
+
+    if (!access(filename, F_OK)) {
+        opal_show_help("help-mpi-btl-openib.txt", "ini file:file not found",
+                       true, filename);
+        ret = OPAL_ERR_NOT_FOUND;
+        goto cleanup;
+    }
+
     btl_openib_ini_yyin = fopen(filename, "r");
     if (NULL == btl_openib_ini_yyin) {
-        opal_show_help("help-mpi-btl-openib.txt", "ini file:file not found",
+        opal_show_help("help-mpi-btl-openib.txt", "ini file:could not open",
                        true, filename);
         ret = OPAL_ERR_NOT_FOUND;
         goto cleanup;

opal/mca/btl/ugni/btl_ugni_init.c

@@ -264,12 +264,13 @@ int mca_btl_ugni_init (void)
         mca_btl_ugni_component.virtual_device_count = MCA_BTL_UGNI_MAX_DEV_HANDLES;
     }
 
-    fh = fopen ("/proc/sys/kernel/pid_max", "r");
-    if (NULL != fh) {
-        fscanf (fh, "%d", &pid_max);
-        fclose (fh);
+    if (access("/proc/sys/kernel/pid_max", F_OK)) {
+        fh = fopen ("/proc/sys/kernel/pid_max", "r");
+        if (NULL != fh) {
+            fscanf (fh, "%d", &pid_max);
+            fclose (fh);
+        }
     }
-
     /* Use pid to generate the cdm_id.  Although its not stated in the uGNI
      * documentation, the cdm_id only needs to be unique within a node for a
      * given ptag/cookie tuple */

opal/mca/crs/blcr/crs_blcr_module.c

@@ -739,6 +739,14 @@ static int blcr_cold_start(opal_crs_blcr_snapshot_t *snapshot) {
      * Find the snapshot directory, read the metadata file
      */
     if( NULL == snapshot->super.metadata ) {
+        if(access(snapshot->super.metadata_filename, F_OK) {
+            opal_output(mca_crs_blcr_component.super.output_handle,
+                        "crs:blcr: checkpoint(): Error: %s does not exist",
+                        snapshot->super.metadata_filename);
+            exit_status = OPAL_ERROR;
+            goto cleanup;
+        }
+
         if (NULL == (snapshot->super.metadata = fopen(snapshot->super.metadata_filename, "r")) ) {
             opal_output(mca_crs_blcr_component.super.output_handle,
                         "crs:blcr: checkpoint(): Error: Unable to open the file (%s)",

opal/mca/crs/dmtcp/crs_dmtcp_module.c

@@ -477,13 +477,14 @@ static int dmtcp_cold_start(opal_crs_dmtcp_snapshot_t *snapshot) {
     char **tmp_argv = NULL;
     char * component_name = NULL;
     int prev_pid;
-
+    char *smfname;
     /*
      * Find the snapshot directory, read the metadata file for
      * component name and previous pid
      */
     if( NULL == snapshot->super.metadata ) {
-        if (NULL == (snapshot->super.metadata = fopen(snapshot->super.metadata_filename, "r")) ) {
+        smfname = snapshot->super.metadata_filename;
+        if (!access(smfname, F_OK) || NULL == (snapshot->super.metadata = fopen(smfname, "r")) ) {
             opal_output(mca_crs_dmtcp_component.super.output_handle,
                         "crs:dmtcp: dmtcp_cold_start(): Error: Unable to open the file (%s)",
                         snapshot->super.metadata_filename);

opal/mca/if/linux_ipv6/if_linux_ipv6.c

@@ -95,7 +95,8 @@ static int if_linux_ipv6_open(void)
 {
 #if OPAL_ENABLE_IPV6
     FILE *f;
-    if ((f = fopen("/proc/net/if_inet6", "r"))) {
+    if (access("/proc/net/if_inet6", F_OK) &&
+        (f = fopen("/proc/net/if_inet6", "r"))) {
         char ifname[IF_NAMESIZE];
         unsigned int idx, pfxlen, scope, dadstat;
         struct in6_addr a6;